Gravity Thickener

The new Gravity Thickener Facilities are designed to reduce odor emissions from existing Set 2 Primary Sedimentation Tanks (PSTs) at the Northeast Water Pollution Control Plant. All existing primary sludge pumps were replaced to continually pump settled solids out of the existing PSTs into four 80-foot diameter gravity thickeners. Thickened sludge will collect in a wet well and be pumped into an existing well located in the Sludge Thickener Building, mixed with thickened biological solids and pumped to the digesters. Odorous air will then be exhausted from the facilities into a bio-filter odor control system.

Thomas P. Carney, Inc. work includes construction of a new Gravity Thickener Building, Odor Control Facility, Gravity Thickener Overflow Valve Vault, and Digested Sludge Transfer Pumping Station, installation of diluting water line, sodium hypochlorite system and replacement of Set 1 and Set 2 Primary Sludge Pumps and Mixed Sludge Pumps. Electrical, Mechanical and Plumbing work are performed under the General Construction contract.

All construction work is being performed with minimal interruption to the daily operation of the Water Pollution Control Plant.